The use of printed circuit boards, both single sided and double sided, and similar devices in the electronics industry is well known. Often printed circuit traces on such boards are terminated at holes in the printed circuit board. For a single sided board, a trace typically is terminated at a connection or solder pad adjacent the hole, but usually there is no plating or metal in the hole itself. For a double sided board usually the trace is terminated at a plated through hole. Connection of a particular connector or electronic device is made with such traces by respective contacts or leads that are placed in such holes. The mechanical and electrical connections made at such holes often are secured by soldering the leads or contacts and the electrically conductive material at, proximate and/or in a respective hole.
One type of connector device used for connecting the traces on a printed circuit board with other circuitry or devices is known as a header. A header has a plurality of pin contacts or leads that are held in parallel spaced apart relation, generally electrically isolated from each other, by an electrically non-conductive body which usually provides both strain relief and electrical insulation functions. Exemplary spacing of such pin contacts may be on the order of about 0.010 inch, and this gives an idea of the relatively small size of the electrical connector of the present invention. On one side of the header body the head pin contacts are placed in the mentioned holes in the printed circuit board; and on the other side of such body, the header pin contacts are exposed for connection to another electrical connector, e.g. of a cable termination assembly or the like. Such exposed header pin contacts typically extend either normal to the printed circuit board surface or at another angle relative to such surface, including generally parallel thereto.
One problem encountered when connecting an electrical connector to header pin contacts that extend generally in parallel to the surface of a printed circuit board has been that torsional forces or stress applied to the solder connections at the aforementioned holes could weaken or break such connections. Such stress could be derived from the electrical connector as it is installed on or removed from such header pin contacts or even while such electrical connector is in place, for example, via a cable to which the electrical connector it is attached.
For single sided boards the solder connection usually is between the solder pads and the pin contacts. Since the holes adjacent the pads and in which the pin contacts are placed are not plated through, solder will not ordinarily flow into the holes. Adequate space is provided in the holes to permit insertion of the respective pin contacts therein before soldering. Thus, a torsion or rotating type force applied to the pin contacts may tend to rock the pins in the holes or otherwise to move the pin contacts and, thereby, break the solder connection. Such rocking could happen too easily especially when the header is of the type having the contacts extending parallel to the surface of the printed circuit board, during the installation of an electrical connector in connection with the header. Although the solder would tend to flow into plated through holes of a double sided printed circuit board to provide a stronger mechanical connection of a pin contact in that hole than would be obtained typically for single sided boards, it would be helpful to minimize stress applied to the pin contacts of such headers even for double sided boards.
Another difficulty encountered in the header pin contacts/electrical connection arrangements currently used is the assurance of proper alignment of the electrical connector with respect to the header pin contacts so that correct connections between the header pin contacts and corresponding contacts in the electrical connector will be made and so that damage due to misalignment or incorrect connection will be avoided.
Further, a difficulty encountered in several header pin contacts/electrical connection arrangements is the possibility that the electrical connector might disconnect from the header pin contacts, for example in the case of being subjected to vibrational forces. Such vibrational forces may occur in an automobile or other vehicle.